With rapid development of mobile communications technologies, generally a mobile communication system can provide data communication services in addition to basic voice communication services. A user equipment may use the data communication services, which are provided by the mobile communication system, to upload and download various kinds of data. However, generally existing manners of mobile communication services are all to perform data transmission for a single user equipment. Even if other enhanced communication means are used to increase reliability and/or a throughput rate of data transmission of a user equipment, for example, coordinated multipoint transmission (CoMP) is used to increase reliability of data transmission of a user equipment located at a cell edge, and carrier aggregation (CA) is used to increase a throughput rate of the user equipment, operations are still targeted at a single user equipment. When an environment of a user equipment deteriorates, a throughput rate and/or reliability of data transmission of the user equipment decreases dramatically.
To solve the foregoing problem, a concept of cooperative communication, namely, cooperative communication between a single network node and multiple users, which is also referred to as multi-user cooperative communication (MUCC), is put forward. In a cooperative communication architecture, data sent by an eNB (evolved Node B) to a UE (user equipment) may be first sent to another UE near to the UE, and then forwarded to a final destination UE by using a short-range communications technology between the UEs. In this way, a UE having a best channel condition may be selected from several UEs for delivery, to achieve an effect of multi-user diversity. Existing cooperative communication has the following disadvantages: In a cooperative communication process, a UE (benefited UE or supporting UE) may need to be handed over to a new eNB due to deterioration of a channel condition or other reasons, and in this case, an existing cooperative communication relationship cannot be released or maintained during the handover in the prior art.